package cn.bittonet.wftpay.felonehelper.utils;

import android.content.Context;
import android.support.annotation.NonNull;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.view.ViewGroup;


public class FullyGridLayoutManager extends GridLayoutManager {

    public FullyGridLayoutManager(Context context, int spanCount) {
        this(context, spanCount, GridLayoutManager.VERTICAL, false);
    }

    public FullyGridLayoutManager(Context context, int spanCount, int orientation,
            boolean reverseLayout) {
        super(context, spanCount, orientation, reverseLayout);
    }

    private int[] mMeasuredDimension = new int[2];

    @Override
    public void onMeasure(@NonNull RecyclerView.Recycler recycler,
            @NonNull RecyclerView.State state, int widthSpec, int heightSpec) {
        final int widthMode  = View.MeasureSpec.getMode(widthSpec);
        final int heightMode = View.MeasureSpec.getMode(heightSpec);
        final int widthSize  = View.MeasureSpec.getSize(widthSpec);
        final int heightSize = View.MeasureSpec.getSize(heightSpec);

        int width  = 0;
        int height = 0;
        int count  = getItemCount();
        int span   = getSpanCount();
        for (int i = 0; i < count; i++) {
            measureScrapChild(recycler, i,
                              View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
                              View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
                              mMeasuredDimension);

            if (getOrientation() == HORIZONTAL) {
                if (i % span == 0) {
                    width = width + mMeasuredDimension[0];
                }
                if (i == 0) {
                    height = mMeasuredDimension[1];
                }
            } else {
                if (i % span == 0) {
                    height = height + mMeasuredDimension[1];
                }
                if (i == 0) {
                    width = mMeasuredDimension[0];
                }
            }
        }

        switch (widthMode) {
            case View.MeasureSpec.EXACTLY:
                width = widthSize;
            case View.MeasureSpec.AT_MOST:
            case View.MeasureSpec.UNSPECIFIED:
        }

        switch (heightMode) {
            case View.MeasureSpec.EXACTLY:
                height = heightSize;
            case View.MeasureSpec.AT_MOST:
            case View.MeasureSpec.UNSPECIFIED:
        }

        setMeasuredDimension(width, height);
    }

    private final RecyclerView.State mState = new RecyclerView.State();

    private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec,
            int heightSpec, int[] measuredDimension) {
        int itemCount = mState.getItemCount();
        if (position < itemCount) {
            try {
                View                      view = recycler.getViewForPosition(0);
                RecyclerView.LayoutParams p    = (RecyclerView.LayoutParams) view.getLayoutParams();
                int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, getPaddingLeft()
                        + getPaddingRight(), p.width);
                int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, getPaddingTop()
                        + getPaddingBottom(), p.height);
                view.measure(childWidthSpec, childHeightSpec);
                measuredDimension[0] = view.getMeasuredWidth() + p.leftMargin + p.rightMargin;
                measuredDimension[1] = view.getMeasuredHeight() + p.bottomMargin + p.topMargin;
                recycler.recycleView(view);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}
